Major portions of the laminating adhesives industry such as, for example, the construction adhesives industry require a laminating adhesive to permanently bond films and foils including plastic films such as, for example, plasticized polyvinyl chloride films and cellulosic foils such as, for example, decorative (printed) paper foils to construction substrates. Construction substrates include porous substrates such as, for example, particle board, plywood, hardboard, pressboard, chipboard, fiberboard, and strandboard.
Present adhesives cannot achieve a useful balance of high temperature and ambient temperature property performance in a one-part adhesive composition. In a one-part adhesive composition, a relatively hard copolymer will deliver adequate high temperature performance; however, ambient temperature performance may be inadequate. Adding a plasticizer to a relatively hard copolymer improves the ambient temperature adhesive performance but only with attrition in high temperature adhesive performance.
One solution to this problem is to employ a two-part adhesive composition in which at least one reactive copolymer is mixed with a second reactive agent, which may be low in molecular weight or polymeric. Such two-part systems are problematic in terms of handling, expense, and stability of the admixed composition.
We have now found that aqueous laminating construction adhesive compositions incorporating a one-part adhesive copolymer, the copolymer being a vinyl ester/acrylic copolymer containing from about 0.1% to about 20%, by weight based on copolymer weight, of a copolymerized polar monomer, the copolymer having a Tg from about 10 C. to about -35 C., preferably from about -5 C. to about -25 C., exhibit a good balance of high temperature and ambient temperature adhesion performance in a one-part adhesive composition.